Method of producing insulating material



March 26, 1935. H. M. GAARDER 1,996,043

METHOD OF PRODUCING INSULATING' MATERIAL Filed March 15, 1933 Patented Mar. 26, 1 935 UNITED STATES METHOD. or

yHerbert M. Gaarder, Chicago, Ill., assignor to `Wilson` & Co. Inc., f v offDelaware v Application March 15, 7 2 claims.

'Ihis invention consists in a method of profv ducing aninsulating material and the product thereof.

This method is designed forr the manufacture of the vproduct described and claimed `in the co-y the accom- The insulating material is'v mainlyhogs hair.`

The individual hairs run from 1% to 3 long and are quite stili. In forming lthe insulation, the hair is Washed, deodorized and then is thoroughly interlaced by known machinerynand formed into loose blocks of sizes usually Vemployed in insulation, i. e., 1x3"and from 1" to 6" or 8" thick.' The hair is used in an amount varying from 4 to 10 ounces per board foot, the optimum for insulating purposes being about 7 ounces.

The material is held in or compressed into reticulated metal boxes or'molds 1 which comprise the sides 2 and are tted at top and bottom withgwire screens 3.v These molds determine the final shape of the block 4, which is shown in Fig. 4. Clips 15 hold the molds together.

The insulating blocks having been thus formed and shaped are then dipped in a solution of about 20% asphalt and 80% solvent. Carbon tetrachloride is preferred as the solvent because of its non-inflammability.r This dipping may be carried out in the container .5 in which the molds containing the hairs are stacked and into whichy the solution is owed untilthe molds are submerged. The solution is then withdrawn and the blocks drained until the excess solvent has all been removed. It is preferred to carry out the drainngin a closed containerin order to prevent substantial evaporation l of the solvent. Following the draining, the solvent is then evaporated by steam. This operation is carried out by introducing steam into the containerv 5. The

commingled steam and solvent are removedr through the condenser` 6 in order to recover the solvent. By carrying outfthe evaporation of the solvent with steam, the strain. or; compression of the confined hair is relaxed and the individualv hairs acquire a permanent set 4in the position occupied by them. 'Ihe steaming is carried on co- 'f Chicago, Ill., a corporation 1933, serial No. 660,979

(el. 13-4s) PRoDUcING INSULATING MATERIAL piously, until the entireA massv has been well l steamed. l The block of insulating material may then be released from the mold and retains the shape of the receptacle, even to the extent of clearly showing the marks of theA Wire 3. This effect is indicated in Fig. 4 by thel depressions 7. a The steam yis preferably introduced from the top as through the pipe 9, the effect being when so introduced that a large proportion of the s ol-` vent is displaced bythe steam Without permanentevaporation and iiows out molds.

the bottom of they f In the illustration, 10 isrthe solutionstorage tanky from which the lsolution flows" into the chamber 5 through the'line 11, and may be removed `through the line 12 to the receiver 13. The line 14 is an overow line for the solution.

When the operation is completed, the insulating slab contains about 15% of asphalt and 85% hair Aby Weight. The block is quite rigid, has no tendency to spall off or break up under any ordi nary conditions including violent change of temperature, has very little aiiinity for moisture, and has an insulating value substantially equal to the bestv cork. `It is very much lighter than other insulators, is very little attacked by rats, and affords an outlet for the'hi product-of the meat packing industry.

Commercial blocks are made as described and shipped `Without the need for any other coating orprotection. When they are about to be used, they are ordinarily dipped in melted asphalt. Such is the density and structure of the lblock that the melted asphalt `penetrates only about one-sixteenth of an inch, thus forming outer4 ythoroughly impermeable coatings 8 as illustrated in the drawing, Without any change in the inte?v rior body of the block.

The foregoing damned description has beenV given for clearness of understanding only, and no. unnecessary limitations should be Iunderstood therefrom, but the appended claims should ybe therto largely useless Y construed as broadly as permissiblejn view'of the v prior art.

`What I regard as new, and desirey to secure by` Letters Patent, is:

l. 'I'heymethod ofA preparing an insulating block which comprises interlacing hog hair,l

shaping said hair to'form a block, immersing said block in a solution of an asphalt binder,

draining off vexcess solution, and'steaming the block to removeremaining solventand set the the solution of the binder comprises 20% asphalt and l80% lcarbon tetrachloride.

2. The method set forth' in 01mm i, in which HERBERTA M. Gananirrt,.-l 

